1. Technical Field
Example embodiments generally relate to a fixing device and an image forming apparatus, and more particularly, to a fixing device for fixing a toner image on a recording medium and an image forming apparatus incorporating the fixing device.
2. Background Art
Related-art image forming apparatuses, such as copiers, facsimile machines, printers, or multifunction printers having two or more of copying, printing, scanning, facsimile, plotter, and other functions, typically form an image on a recording medium according to image data. Thus, for example, a charger uniformly charges a surface of a photoconductor; an optical writer emits a light beam onto the charged surface of the photoconductor to form an electrostatic latent image on the photoconductor according to the image data; a development device supplies toner to the electrostatic latent image formed on the photoconductor to render the electrostatic latent image visible as a toner image; the toner image is directly transferred from the photoconductor onto a recording medium or is indirectly transferred from the photoconductor onto a recording medium via an intermediate transfer belt; finally, a fixing device applies heat and pressure to the recording medium bearing the toner image to fix the toner image on the recording medium, thus forming the image on the recording medium.
Such fixing device may include an endless belt having a decreased thermal capacity to shorten a warm-up time taken to warm up the fixing device to a desired fixing temperature and a first print time taken to output the first recording medium bearing the fixed toner image upon receipt of a print job.
For example, the belt is formed into a loop inside which a stationary nip formation pad is situated. A pressing roller situated outside the loop formed by the belt is pressed against the nip formation pad via the belt to form a fixing nip between the pressing roller and the belt. As the belt and the pressing roller rotate and convey the recording medium through the fixing nip, the belt and the pressing roller apply heat and pressure to the recording medium, fixing the toner image on the recording medium.
Since the pressing roller presses the belt against the nip formation pad, as the belt rotates, it slides over the nip formation pad frictionally, resulting abrasion of the belt and the nip formation pad. To address this problem, a low-friction sheet having a decreased friction coefficient may be interposed between the belt and the nip formation pad. For example, JP-2010-181821-A discloses the low-friction sheet sandwiched between the belt and the nip formation pad so that the belt slides over the nip formation pad via the low-friction sheet. The low-friction sheet covering the nip formation pad is secured to the nip formation pad with a plate spring and a screw. The low-friction sheet reduces friction between the belt and the nip formation pad, suppressing abrasion of the belt and the nip formation pad.
However, the plate spring and the screw may occupy a substantial space which upsizes the fixing device and complicate assembly of the fixing device which increases manufacturing costs.